This invention relates to background lighting apparatus and more particularly to thin background light sources for liquid crystal panel displays such as employed in computers, word processors and LCD television sets and the like.
In Japanese Laid Open No. 63-62105, there is described a background light system in which the irregular reflecting surface is provided with a pattern of milky white type net points on a transparent plate supported in the housing unit of the liquid crystal display. However, the luminous efficiency of this type of reflecting surface is low when employed in the rear portion of the liquid crystal display housing unit. In order to increase the brightness, a plurality of superimposed transparent plates are utilized each with a net point pattern. However, the thickness of the display becomes large and the dispersion of light and resulting brightness in the reflecting surface or multiple surfaces of the transparent plates is not achieved resulting in unevenness or nonuniformity in brightness in back lighting and in the displayed image.
It is an object of this invention to provide a background lighting apparatus for liquid crystal display panels, or other such displays requiring background lighting, that achieves high luminous efficiency with high flat brightness dispersion utilizing only one thin transparent plate in the apparatus.